why do i fantasize of people beating me up and then someone watching it and feeling sorry for me and helps me? and why when someone is nice to me or gives me a compliment or is interested in me i become obsessed with them? And i want bruises all over my body so someone can feel sorry for me.
It all sounds like you are desperately craving love and protection. And maybe you've been very hurt either emotionally, physically, or both in your life, and either nobody came to your rescue - or maybe somebody did step up and show some kindness after you got hurt, so you connect the experience of someone feeling sorry for you, with the experience of being loved.
The truth of course, is that you deserve to be loved and protected and cared for just as you are. You don't have to be bruised or bleeding or even sad in order to receive love or kindness. You are worthy of that at all times. And only by learning to love and accept yourself as you are, can you begin to ask for and receive what you want from others.
If you have past traumas, hurts done to you, maybe neglect in your past, then getting the help of a good therapist or EFT Tapping practitioner who specializes in trauma, would probably be a great help to resolving this and increasing your self worth.
Wishing you happiness and self acceptance.